Commits
H.J. Lu committed 55283e25377
x32: Add ptrace for x32 X32 ptrace is a hybrid of 64bit ptrace and compat ptrace with 32bit address and longs. It use 64bit ptrace to access the full 64bit registers. PTRACE_PEEKUSR and PTRACE_POKEUSR are only allowed to access segment and debug registers. PTRACE_PEEKUSR returns the lower 32bits and PTRACE_POKEUSR zero-extends 32bit value to 64bit. It works since the upper 32bits of segment and debug registers of x32 process are always zero. GDB only uses PTRACE_PEEKUSR and PTRACE_POKEUSR to access segment and debug registers. [ hpa: changed TIF_X32 test to use !is_ia32_task() instead, and moved the system call number to the now-unused 521 slot. ] Signed-off-by: "H.J. Lu" <hjl.tools@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Roland McGrath <roland@hack.frob.com> Cc: Oleg Nesterov <oleg@redhat.com> Link: http://lkml.kernel.org/r/1329696488-16970-1-git-send-email-hpa@zytor.com